Adam Tobit
15/1/11
Block - D
Big Idea - Many important practical & mathematical applications involve comparing quantities of one kind or another; it is important to know which method to use & how we should use them.

Essential Question - Which comparing strategies work best in which situations?
Notes -
You start off with making it a unit rate.
Problem 6.2 – Using Rules of Thumb
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A. It takes about 100 maple trees to make 25 gallons of maple syrup. Mr. Paulo made maple syrup from all of his sugar maple trees. He ended up with 16 gallons of syrup. About how many sugar maple trees does he have?
He has 64 maple trees because if you make it a unit rate and then multiply it by 16 you get 64.
B. A 5-minute shower requires 18 gallons of water. About how much water do you use for an 8-minute shower? How much water will you use if you take an 8-minute shower for everyday of the year?
28.8 Gallons of water would be needed for an 8-minute shower. 10,512 gallons would be needed for 8-minute showers for everyday of the year. I got this by making it a unit rate and then multiplying it by eight and then multiplying that by 365.
C. A double spaced page of text contains about 250 words if it is printed in times with a font size of 12, and about 330 words if it is printed in times with font size 10. Jeremy printed his term paper in the computer lab. He used 10-point Times, and the paper came to be 15 double-spaced pages. Jeremy’s teacher requires term papers be 20 double-spaced pages long. If Jeremy changes the font to 12-point Times, how long would his paper be?
His paper would be 19.8 pages long because if you multiply 15 by 110 and then dividing that by 250 you get 26.4 which is how many pages it will be.
C. Jogging burns about 100 calories per mile. Elizabeth jogs at a rate of 4.5 miles per hour. How long will it take her to burn off the 1200-calorieluch she ate at Burger Heaven?
She would have to jog 2.6667 miles to burn off her calories and she would have burned of 0.015 calories extra. I got this by multiplying 4.5 by 100 and kept multiplying numbers to see which one reaches 1200.

Follow Up
Ask adults you know if they use any rules of thumb in their jobs or at home. Write down one of the rules you learn. Write a problem that can be solved using this rule.
I asked my dad and he told me this – To determine the monthly revenue forecast at any point – The average revenue pre day times 30 days, times 98% is the monthly income.
What is the average revenue fro a month if the average revenue per day is 10?
30 times 10 = 300 Then… 300 times 98/100 = 294
The average revenue for the month is 294


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